#47192 [Com]: gethostbyname is not interruptible by signals

ID: 47192 Comment by: fmassei at gmail dot com Reported By: fmassei at gmail dot com Status: Open Bug Type: Feature/Change Request Operating System: linux PHP Version: 5.2.8 New Comment: Quick and dirty workaround: create a child process for resolving the hostname and let the parent manage the signals. <?php /* signal handling */ declare(ticks=1); function sa($signo) { global $pid; echo "Received signal $signo (with child $pid)\n"; /* check if the pid is zero: thus it will work even if the behaviour of this * function will be fixed in the future. */ if ($pid!=0) posix_kill($pid, SIGKILL); /* the only possible signal */ } /* register the signal */ pcntl_signal(SIGALRM, "sa"); /* get an ipc queue */ if (($sysId = ftok("/tmp/pr", "a"))===-1) die("Could not ftok\n"); $key_t = msg_get_queue($sysId); /* ipc message type based on parent's pid */ $msgtype = posix_getpid(); /* fork */ $pid = pcntl_fork(); if ($pid==-1) { echo "Failed to fork.\n"; exit(1); } else if ($pid==0) { /* child process */ $ip = gethostbyname($hostname); msg_send($key_t, $msgtype, $ip, true, false, $err); exit(0); } else { /* parent process */ pcntl_alarm(5); /* timeout before giving up */ if (msg_receive($key_t, $msgtype, $type, 100, $msg, true, 0, $err)===false) echo("receive failed.\n"); else echo $msg."\n"; pcntl_alarm(0); } /* clean and finish */ msg_remove_queue($key_t); echo "Done.\n"; ?> Previous Comments: ------------------------------------------------------------------------ [2009-01-25 16:00:08] fmassei at gmail dot com well, it actually IS a bug, as long as the "pcntl_" functions are not working as described for this function only. ------------------------------------------------------------------------ [2009-01-24 23:55:06] jani@php.net No, it's a change request since this function is not designed to do what you ask. Not everything is a bug.. ------------------------------------------------------------------------ [2009-01-23 13:52:04] fmassei at gmail dot com Somehow I posted this bug in the wrong category. It's not a "Feature/Change Request" but more a "Network related" bug. ------------------------------------------------------------------------ [2009-01-22 18:13:35] fmassei at gmail dot com Description: ------------ gethostbyname() is not interruptible by signals. If it cannot resolve an hostname there is no way it can be interrupted except for a SIGKILL. Reproduce code: --------------- declare(ticks=1); function al($sig) { echo $sig; exit(0); } pcntl_signal(SIGINT, "al"); pcntl_signal(SIGTERM, "al"); pcntl_signal(SIGALRM, "al"); pcntl_alarm(3); echo gethostbyname("google.com"); Expected result: ---------------- I was expected to interrupt gethostbyname() with any signal. Actual result: -------------- When running the above code, if the system cannot resolve google's hostname, the function blocks and doesn't respond to any signal. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=47192&edit=1